Expand and combine like terms. $(8x^4+1)^2=$
Answer: We can expand this expression using the "perfect square" pattern (where $P$ and $Q$ can be any monomial): $(P+Q)^2=P^2+2PQ+Q^2$ $\begin{aligned} &\phantom{=}\left(8x^4+1\right)^2 \\\\ &=\left(8x^4\right)^2+2\left(8x^4\right)\left(1\right)+\left(1\right)^2 \\\\ &=64x^8+16x^4+1 \end{aligned}$